/Engine/Plugins/Runtime/nDisplay/Source/DisplayCluster/Public/Render/Viewport/RenderFrame/DisplayClusterRenderFrameEnums.h
(experimental, not implemented, reserved)
enum EDisplayClusterRenderFamilyMode { None = 0, AllowMergeForGroups, AllowMergeForGroupsAndStereo, MergeAnyPossible, }